Method for setting horn air gap

Abstract

A method for setting the air gap in an automotive horn having an armature and a stud comprises the steps of positioning the stud through an orifice so that it contacts the armature, backing the stud away from the armature a predetermined distance, and fixing the stud to the horn housing so as to establish the air gap between the armature and the stud.

I claim: 
     
       1. In an automotive horn having a housing and a projector with a diaphragm mounted therebetween, an armature attached to the diaphragm extending into a bore formed by windings of an electromagnetic coil, and an orifice in the housing for allowing a stud member to pass therethrough so as to be in alignment with the armature, a method for setting an air gap between the armature and the stud comprising the steps of: positioning the stud member proximate the orifice;   moving the stud through the orifice toward the armature until contact is made therewith;   moving the stud away from the armature a predetermined distance; and   attaching said stuff to said horn so as to be in a fixed relationship the predetermined distance from said armature.   
     
     
       2. A method according to claim 1 wherein the stud is affixed to said horn by crimping a neck flange extending from said horn and defining said orifice to said stud. 
     
     
       3. A method according to claim 1, wherein said predetermined distance is between approximately 0.5 mm. and 1.5mm., and preferably is 1.0 mm. 
     
     
       4. In an automotive horn having a housing and a projector with a diaphragm mounted therebetween, an armature attached to the diaphragm extending into a bore formed by windings of an electromagnetic coil, and an orifice in the housing for allowing a stud member to pass therethrough so as to be in alignment with the armature, a method for setting an air gap between the armature and the stud comprising the steps of: positioning the stud proximate the orifice so as to move in alignment with the armature, the stud positioned with positioning means for aligning the stud;   moving the stud through the orifice along an axis through the center of the coil toward the armature;   sensing contact between the stud and the armature with sensing means attached to the positioning means;   stopping movement of the positioning means when contact between the armature and the stud is sensed;   moving the stud a predetermined distance away from the armature so as to establish an air gap therebetween; and   attaching the stud to the horn housing so as to fix the air gap between the armature and the stud.   
     
     
       5. A method according to claim 4 wherein the stud is affixed to said horn by crimping a neck flange extending from said horn and defining said orifice to said stud. 
     
     
       6. A method according to claim 4, wherein said predetermined distance is between approximately 0.5 mm. and 1.5 mm., and preferably is 1.0 mm. 
     
     
       7. The method according to claim 4, wherein the positioning means comprises an hydraulically actuated arm. 
     
     
       8. The method according to claim 4, wherein the sensing means comprises a load cell attached to the positioning means. 
     
     
       9. In an automotive horn pre-assembled with a housing and a projector having a diaphragm mounted therebetween, a ferro-magnetic armature attached to the diaphragm extending into a bore formed by windings of an electromagnetic coil, and an orifice through a neck portion of the housing for allowing a ferro-magnetic stud to pass therethrough so as to be in alignment with the armature, a method for setting an air gap between the armature and the stud comprising the steps of: positioning the stud with a hydraulically actuated arm proximate the orifice so as enable movement along an axis through the center of the coil;   moving the stud through the orifice toward the armature;   sensing contact between the stud and the armature with a load cell attached to the hydraulically actuated arm;   stopping movement of the arm when contact between the armature and the stud is sensed;   moving the stud a predetermined distance away from the armature so as to establish an air gap therebetween; and   crimping the neck portion of the housing around the stud so as to fix the air gap between the armature and the stud.   
     
     
       10. The method according to claim 9 wherein the load cell is calibrated such that contact between the stud and the armature does not cause significant deflection of the diaphragm.